The transmission electron microscope (TEM) is a basic tool for ultrastructural studies in neurobiology: the morphology of neurons, glia and synapses can be seen in great detail with the high resolution and magnification provided by this instrument. Observations obtained from the EM analysis of nervous tissues have contributed significantly to the many disciplines of neuroscience, e.g., to developmental neurobiology, neuropathology and the morphophysiology of synaptic transmission. The instrument requested, a Philips EM410LS electron microscope, delivers a very high quality image at a competitive price and it includes a number of important features which we currently lack with our aging equipment. The projected user group, which consists of investigators with proven track records, need a TEM with good resolution at low magnifications (100-5000X), a large throughput of negatives per session (36 images instead of the current 16), and a video output for interface with a newly acquired image analyzer. We have functioned successfully as a multi-user group within the Department of Neuroscience for many years, sharing two TEMs, one for senior investigators and the other for students and junior investigators. Four major user groups are identified. The new TEM will be reserved for five senior investigators and our 13 year old Philips 300 will be used by some senior investigators as well as by postdoctoral trainees and graduate students. Our 25 year old Philips 200 will be retired from service as it no longer functions satisfactorily; our plan is to replace it with the EM 410LS. The new instrument will be used in a diverse group of projects, each representing a discipline of neuroscience cited above. The added capabilities of the new TEM will not only enhance our current research efforts in terms of both efficacy and efficiency, but will potentiate more ambitious scientific goals in the planning of new studies.